//: Playground - noun: a place where people can play

import UIKit

var str = "Hello, playground"

var a: Int
a = 10

var imOptionalVariable :Int?
imOptionalVariable = 12
imOptionalVariable!

let userInput:String = "abc"
//var age = userInput.toInt()
//if age != nil
//{
//    print("your age is " + String(age!))
//}
//else{
//    print("fuck me!")
//}


// optional binding
//if let userAge = userInput.toInt()
//{
//    
//}else{
//    
//}


let strA:String? = "test"
strA
strA!


let strB:String! = "test"
strB
